1. Field of the Invention
The present invention relates to a hemostatic agent composition, delivery system and method. This composition, delivery system and method may be used to deliver a hemostatic agent directly proximate a hemorrhage site and may also be used to dry oozing fluid sites while keeping an area moist preventing re-irritation, such as by bed sores.
More specifically, the invention includes a system for delivering a hemostatic agent to a wound, a hemostatic agent composition, a method of accelerating blood clotting of a wound, a hemostatic agent and delivery system, a bandage to be applied to a wound, oozing blood or other bodily fluids and a bandage to be applied to a narrow wound opening oozing blood or other bodily fluids.
2. Description of Related Art
It has long been known that injuries which result in excessive bleeding if not quickly or properly addressed can often prove fatal. Unfortunately, this fact is well supported by data gathered during numerous armed conflicts throughout time. For instance, it has been reported that over 2,500 soldiers died from extremity wounds during the Vietnam War solely because they bled to death. Military data also indicate that approximately 50% of combat casualties die from bleeding, and that the majority die within thirty minutes of the injury. It has also been reported that of the fifty %, approximately sixty % die within the first five minutes while the remaining persons die within one hour if not properly treated.
In addition, it has been estimated that there are over seventy million emergency room visits each year for bleeding. As above, with respect to injuries sustained during battle, bleeding or acute hemorrhaging is a leading cause of death in trauma cases among the civilian population.
As such, it is clear that rapid and effective control of hemorrhaging saves lives. Attempts to address the need for such rapid and effective hemorrhage control have resulted in a development of a number of so called hemostatic bandages and other products purported to facilitate rapid control of bleeding.
One such product includes a granular zeolite material which may be obtained from volcanic lava rocks. This material is placed into a bleeding wound where it absorbs water molecules from the blood, thereby creating a high platelet concentration which promotes clotting. However, it has been documented that the absorption process affected by this zeolite is a highly exothermic reaction which generates a considerable amount of heat, attributable to reaction with the iron content of the zeolite. More specifically, temperatures ranging from 90° C. to 100° C. have been reported following use of the material, causing second degree burns to soldiers injured and treated with this product in Iraq, as well as to those persons administering the product, even though personnel administering this product must be trained and certified to administer the same.
A further drawback to this product is that the zeolite material is packaged to be simply poured on to an open wound, however, in the case of hemorrhaging of any significance, such as may occur due to laceration of a major artery, the pressure of blood exiting the wound will simply cause the material to be dispersed thereby minimizing and/or eliminating the effectiveness of the clotting properties therein. Another disadvantage is that the zeolite's efficacy is exhausted at first contact with blood such that a clot may be formed distant to the actual wound source without stopping hemorrhaging. Yet another disadvantage of this product is that the zeolite material is granular in nature, making it difficult to subsequently remove the material from the wound via normal measures such as irrigation and/or suctioning of the wound area, once the injured person is transferred to an operating room or other such treatment facility.
Another product is made from chitosan, which is derived from the exoskeletons of shellfish. Reports as to the effectiveness of this device in hemorrhage control are conflicting, in particular, its effectiveness in the event of hypothermia in the patient, such as may occur from shock following significant blood loss, is reported to be severely reduced or diminished. In addition, there have been reports of the device being improperly applied, e.g., the wound is not contacted by the active surface due to the device being placed into the wound site upside down. Since this product is derived from living organisms, it has an extremely limited shelf life during which time it must either be utilized or disposed of, and given the significant cost of each unit, this is a further considerable disadvantage. This product is available in powder form or adhered to a felt material.
Another type of hemostatic bandage is manufactured from single cell algae and includes poly-N-acetylglucosamine. This device is structured to enable persons with minimal training to quickly and effectively control and/or stop hemorrhaging from extremity trauma. More in particular, when the material comes in contact with blood it reportedly stimulates platelet aggregation and activation which causes the body to secrete tromboxane, which stimulates the blood vessels to constrict in the vicinity of the wound. Stated differently, the poly-N-acetylglucosamine material acts as a catalyst to accelerate the normal clotting process thereby accelerating the bodies' own control of the bleeding. Once again, since this product is derived from living organisms, it has a limited shelf life during which it must be utilized or disposed. Further, its effectiveness in the event of hypothermia in the patient, such as in the above example, is questionable.
Another material which is structured to be applied, i.e., poured, directly to wounds has been synthesized from potato starch. Reportedly, the particles accelerate natural clotting by concentrating blood solids forming a gel around the same so as to promote clotting. In particular, the larger particles of the blood components are concentrated on the surface of the synthesized potato starch product, thereby promoting accelerated clotting. As noted, this material is also in a powder form and has been applied directly to a bleeding wound with a bellows type applicator as noted above with respect to the zeolite material, however, in the event of excessive bleeding such as a major artery, the pressure of the blood flowing from the wound is often sufficient to disperse the powder thereby once again, minimizing or eliminating the clotting property exhibited therein, even though the wound site is to be covered with a standard bandage and pressure applied after treatment with the synthesized potato starch material.
Yet another powdered material is composed from a hydrophilic polymer and a potassium salt in combination with a bovine based thrombin material. This powder is also reported to stop bleeding on contact based upon studies for various minor wounds, in which no covering bandage is required, however, as noted above with respect to the other “pour” type products, in the event of any significant bleeding, the blood pressure itself is likely to disperse the product, thereby reducing or eliminating any hemostasis it was intended to effect.
One product patented from TraumaCure (Bethesda, Md.) is a balloon device. A deflated balloon is inserted through the wound entry point and then inflated while in the wound cavity, putting pressure against the wound walls and source of bleeding.
Another type of hemostatic bandage is manufactured using a low absorption, low swell clay material, kaolin, disposed on one side of a substrate of felt material adhered using a polyol binder. Several drawbacks exist with this product including the use of a low absorption clay material which severely limits its speed and capacity in promoting clotting in major arterial bleeding wherein time is critical in terminating hemorrhaging. Due to the low absorption capacity and its tight weave substrate, its efficacy is exhausted at first contact with blood such that a clot may be formed distant to the actual wound source without stopping hemorrhaging. Kaolin molecules swell at first contact with blood creating an impenetrable barrier to further absorption. The clay also does not contain a beneficiating agent such as a dispersal agent to optimize absorption. Additionally, the tight weave of the felt-like fabric which is required because of the limitations of its adhesion capability restrict even further the amount of clay material able to be disposed on it. In addition, the end product created by the disposition of the kaolin on this felt-like material creates a very stiff fabric which does not easily form to the wound irregularities. The stiff fabric does not allow for insertion into narrow wound openings. The closed weave fabric does not allow for percolation of the water content of the blood through the fabric layers further limiting efficacy.